The aquarium filter media ring is suitable for fresh water and sea water tank. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. This product can be used in a variety of filters, pls place in the appropriate position of the filter. Features: The aquarium filter media ring is fired by high temperature. Full of rich variety of natural elements and essential minerals and trace elements. Encourages growth of biological colonies and holds large amounts of good bacteria. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. Suitable for fresh water and sea water tank. Reduces ammonia and nitrate levels. Any problem, please contact our store without hesitation. Honor to serve you! Specification: Name: Aquarium filter media ring Material: Quartz Size: Length: 1.6cm, diameter: 1.6cm Package Information: Package size: 20 * 15 * 8cm / 7.87 * 5.90 * 3.15in Package weight: 391g Plastic Packaging Package List: 100* Aquarium filter media ring